Forbes Media will cut 30 to 40 people from its depleted editorial ranks over the next three days, as its magazine braces for losses, sources said.

“We — and the entire media world — have been hit hard by the severe recession and the seismic shifts wrought by the Web,” Chairman Steve Forbes said in a memo announcing the third round of layoffs this year.

The move comes three years after Elevation Partners, which counts U2 singer Bono and Silicon Valley investor Roger McNamee as managing directors, paid an estimated $250 million to $300 million for what is believed to be a 40 percent stake of the Forbes family’s media holdings.

Earlier this year, McNamee stepped down from Forbes Media’s board, saying Forbes.com was no longer offsetting declines in the print business.